- Joined
- Aug 16, 2019
- Messages
- 65
i have been facinated by old nortons and there sporty heritage since i was a boy and had several over the years .
I have always had a hankering to build a demodromic norton not like some unobtainable surtees /works one but i thought with a lttle help from mr Taglioni ala Ducati id have a go ! he stole the idea from JL Norton anyway didnt he ?
no fancy castings here , fortunately i have great wealth of experience welding aluminium and a few machinist pals
took some 57 es2 crankcases
welded up the mouth added plate on drive side welded up stud holes relocated/widened stud centres
built up timing side bearing boss to take a twin row bearing then re machined the lot to take a modded Jawa crank
a klr 650 kwacker piston and liner was machined and fitted to a manx casting with a billet spacer under it
the liner has recently been machined on the top to accept a copper nickel sealing wire ring that cured copper gasket trouble
next up take an old 52 350 manx head casting and weld the chamber up to mimic a modern manx bathtub squish head and dill and tap for 2 10mm plugs
butcher a bevel 900 ss head by cutting off the cambox and after much mucking around weld it to manx head
i steepend the inlet angle which caused much grief wit rocker geometry and have hardened roller on end of rockers to help stem scuffing
drive is from magneto sprocket to a pair of triumph twin timing gears the top sprocket is welded to tha back of the lower one this drives the cam 'imola with a bit of stellite here and there
chaincase is welded aluminium and gears are caried on a steel section which bolts together all made of scrap
a boss was welded over the outer timing cover and machined flat an extended exhaust cam spindle carries the boyer unit ,ex commando ,timed at 28 degrees
compression is high at 11.5
its over 660 cc 100 mm bore
and kickstarting is possible for the brave
there is also an engine speed rotating armature magneto driven off the crank on the drive side as a get you home back up
if the battery for boyer goes flat
gearbox is a regular amc norton 4 speeder with scarbrough 1st gear
frame is was a late damaged manx with oil in lh tube it now has a yamaha steering head and xs650 forks swining arm is made in high srength 6mo stainless nice but heavy wheels are drz suzuki super moto "great brakes and grip ,
and frame is flanged so take out the 8 rolls royce merlin prop drive bolts and front engine bolt and whel the whole front end away for eay spannnering !
it goes very well , its a big torque job
at the moment the valve timing is fairly advanced for bottom end ,,and revs to 7200 i have had it revving to 8500 before on retarded valve timing on a lower compression with a spacer under the barrel to get the valve pocket clearence
its fine for a little blast round round the block but if i want more reves i have to get a piston with enough meat to machine the pocket deeper by around 3mm
carb is a 40mm dellorto pumper
there a little pphoto on my avatar ,ive not sussed out how to upload photos on this site yet as im an old dino
hope you like it lots,more ideas ahead
i
I have always had a hankering to build a demodromic norton not like some unobtainable surtees /works one but i thought with a lttle help from mr Taglioni ala Ducati id have a go ! he stole the idea from JL Norton anyway didnt he ?
no fancy castings here , fortunately i have great wealth of experience welding aluminium and a few machinist pals
took some 57 es2 crankcases
welded up the mouth added plate on drive side welded up stud holes relocated/widened stud centres
built up timing side bearing boss to take a twin row bearing then re machined the lot to take a modded Jawa crank
a klr 650 kwacker piston and liner was machined and fitted to a manx casting with a billet spacer under it
the liner has recently been machined on the top to accept a copper nickel sealing wire ring that cured copper gasket trouble
next up take an old 52 350 manx head casting and weld the chamber up to mimic a modern manx bathtub squish head and dill and tap for 2 10mm plugs
butcher a bevel 900 ss head by cutting off the cambox and after much mucking around weld it to manx head
i steepend the inlet angle which caused much grief wit rocker geometry and have hardened roller on end of rockers to help stem scuffing
drive is from magneto sprocket to a pair of triumph twin timing gears the top sprocket is welded to tha back of the lower one this drives the cam 'imola with a bit of stellite here and there
chaincase is welded aluminium and gears are caried on a steel section which bolts together all made of scrap
a boss was welded over the outer timing cover and machined flat an extended exhaust cam spindle carries the boyer unit ,ex commando ,timed at 28 degrees
compression is high at 11.5
its over 660 cc 100 mm bore
and kickstarting is possible for the brave
there is also an engine speed rotating armature magneto driven off the crank on the drive side as a get you home back up
if the battery for boyer goes flat
gearbox is a regular amc norton 4 speeder with scarbrough 1st gear
frame is was a late damaged manx with oil in lh tube it now has a yamaha steering head and xs650 forks swining arm is made in high srength 6mo stainless nice but heavy wheels are drz suzuki super moto "great brakes and grip ,
and frame is flanged so take out the 8 rolls royce merlin prop drive bolts and front engine bolt and whel the whole front end away for eay spannnering !
it goes very well , its a big torque job
at the moment the valve timing is fairly advanced for bottom end ,,and revs to 7200 i have had it revving to 8500 before on retarded valve timing on a lower compression with a spacer under the barrel to get the valve pocket clearence
its fine for a little blast round round the block but if i want more reves i have to get a piston with enough meat to machine the pocket deeper by around 3mm
carb is a 40mm dellorto pumper
there a little pphoto on my avatar ,ive not sussed out how to upload photos on this site yet as im an old dino
hope you like it lots,more ideas ahead
i
